圆盘旋转爆震燃烧室中爆震波传播模态

Propagation Mode of Detonation Wave in a Plane-Radial Rotating Detonation Combustion Chamber

关键词:  径向长度  内外直径比值  传播模态  数值模拟  旋转爆震  燃烧室

Key words:  Radial length  Inlet and outer diameter ratio  Propagation mode  Numerical simulation  Rotating detonation  Combustion chamber

摘要:

为了研究圆盘结构下旋转爆震波传播特性，通过求解14组分19步CH₄/O₂反应的欧拉方程，数值模拟了不同燃料喷射温度、压力、燃烧室内外直径比值和燃烧室径向长度并分析了其对旋转爆震波传播模态的影响。研究表明，只有预混气喷射温度为500~900K，喷射压力为0.5~3.5MPa的条件下能够在固定燃烧室内形成连续的旋转爆震波。受燃烧室结构影响，旋转爆震波的传播模态分为稳定模态和非稳定模态。整个非稳定传播模态根据爆震波对前周期的干涉又可以分为干涉阶段和不干涉阶段。在不干涉阶段，爆震波传播速度略高于C-J（Chapman-Jouguet）速度；在干涉阶段，爆震波传播速度低于C-J速度且爆震波被间断面分割成两部分。非稳定模态爆震波传播速度小于稳定模态，而爆震波夹角、燃烧室出口面积比则反之。

Abstract:

In order to study the propagation characteristics of the rotating detonation wave in a plane-radial rotating detonation combustor， Euler equation with 14 species-19 reactions methane/oxygen reaction mechanism were solved. Numerical simulations were conducted to study the effects of injection temperature，pressure，inlet and outer diameter ratio and radial length on the rotating detonation wave propagation mode. The results show that a continuous rotating detonation wave is formed in the fixed combustion chamber with the pre-mixed injection temperature of 500~900K and the injection pressure of 0.5~3.5MPa. With the effect of the combustor structure， propagation modes of rotating detonation waves are divided into stable mode and unstable mode. The entire unstable propagation mode can be divided into two stages based on the interference of the detonation wave to the previous period： the interference stage and the non-interference stage. In the non-interference stage， the propagation speed of the detonation wave is higher than the C-J （Chapman-Jouguet） speed. In the interference stage， the propagation speed of the detonation wave is lower than the C-J speed， and the detonation wave is divided into two parts by the discontinuous surface. The propagation speed of the detonation wave in the stable mode is higher than that in the unstable mode， while the angle of detonation wave and combustor outlet area ratio are reversed.